Infrared ray equipment



Feb. 14, 1950 R. w. LASHELLS 2,497,676

INFRARED RAY EQUIPMENT Filed March 27. 1946 5 Sheets-Sheet l INVENTUR.

1950 R. w. LASHELLS 2,497,676

INFRARED RAY EQUIPMENT Filed March 27, 1946 s Sheets-Sheet 2 LII AW IIIN V EN TOR.

Feb. 14, 1950 w, s s 2,497,676

' INFRARED RAY EQUIPMENT Filed March 27. 1946 s Sheets-Sheet 5 PatentedFeb. 14, 1950 UNITED STATES PATENT OFFICE INFRARED RAY EQUIPMENT RalphW. Lashellsfliindlay, Ohio Application March 27, 1946, Serial No.657,395 1 Claim. (01. 219-34) i This invention relates to infrared rayequip ment and particularly to equipment employing infrared ray lampsfor the purpose of heating objects of various character and for variouspurposes, the principal object being the provision of equipment of thistype capable of conserving electrical energy, providing a more evendistribution of the heat from the infrared ray lamps, and that isreadily adapted to various sizes and shapes of objects to be subjectedto the rays of infrared ray lamps.

Objects of the invention include the provision of a reflector structurefor an infrared ray lamp by means of which a more efflcient distributionof the heat rays from an associated infrared ray lamp is possible thanin constructions heretofore employed; the provision of equipment of thetype described including a reflector so constructed and arranged as topermit a more eflicient reflection of heat rays from an infrared raylamp either directly or indirectly associated therewith than in priorart structures; the provision, in equipment of the type described, of areflecting device for association with an infrared ray lamp soconstructed and arranged as to be capable of directing heat rays from adirectly associated lamp simultaneously upon the opposite ends of a bodywhich ends are spaced from each other by a distance greater than themaximum diameter 'of the lamp; the provision of a reflecting device ofthe character described provided in extended lengths and capable ofreceiving a plurality of infrared ray lamps in association therewith;and the provision of a reflector of the type described of a more or lesscontinuous conformation and 1-;

adapted for a direct association with a plurality of laterally spacedinfrared ray lamps, and a plurality of such reflectors and associatedlamps being adapted to form banks of such lamps by arranging them withthe reflectors in edge to edge relationship.

The above being among the objects of the present invention, the sameconsists in certain novel features of construction and combinations ofparts to be hereinafter described with reference to the accompanyingdrawings, and then claimed, having the above and other objects-in View.I

In the accompanying drawings which illustrate suitable embodiments ofthe present invention and in which like numerals refer to like partsthroughout the several difierent views.

Fig. l is a vertical sectional view taken transversely through areflector-constructed in "accordance with the present invention,illustrating an infrared ray-lamp in association therewith andillustrating the reflection of heat rays from the infrared ray lamp bythe reflector upon an object to be heated,

Fig. 2 is a view similar to Fig. 1, but illustrating a pair of suchreflectors and associated lamps in opposed relationship with respect toeach other and illustrating the heat rays emanating from the lamps andreflected by the reflector,

Fig. 3 is an end elevational view illustrating a typical arrangement inwhich two banks of infrared ray lamps equipped with reflectorsconstructed in accordance with the present invention are arranged inopposed relationship with respect to each other and upon opposite sidesof a conveyor mechanism by means of which work may be caused to be movedbetween the banks,

Fig. 4 is a reduced face view of one of the banks, shown in Fig. 3, butwith the infrared ray lamps removed therefrom, and,

Figs. 5, 6, '7 and 8 are reduced views, similar to Fig. l, butillustrating the application of different types of infrared ray lamps toreflectors con- .structed in accordance with the present inven- .tion.

In infrared ray lamp equipment employed for .drying painted coatings onobjects, or for any other reason, it is desirable, from a commercialstandpoint, that such equipment be made up .mainly from standard partswhich may be assembled to one another to form completed structures ofvarious sizes and shapes adapting them to a relatively wide variation inuses, and sizes and shapes of objects being treated thereby. Otherwise,it would require special parts for each installation with correspondingincreased costs of parts and increased time required to construct thesame.

Additionally, part of such infrared ray lamp equipment desirablyprovides reflecting surfaces for the infrared rays emanating from thelamps. This is true because of the fact that many infrared ray lamps arenot equipped with their own reflectors, that is, silvered surfacesincorporated as a part of the bulb itself, and therefore require forefiicient operation some means for directing the heat rays therefromupon the work. Even in those cases where the bulbs are provided withtheir own reflecting surfaces, inasmuch as such :bulbs are usuallyarranged in opposed banks or series such reflecting surfaces aredesirabl in each bank or series to reflect the heat received therebyfrom the bulbs of the opposite bank or series. Such reflecting surfacesare, of course,

preferably such'as to resultin an even concentratiom or'. diffusion ofboth the reflected and the to strike all surfaces of such object whensuch. object is of a greater siz than the maximum di'-' ameter of thelamp. It will be appreciatedlthat the value of providing such areflecting surface is that certain sizes of objects, of a maximum"dimension between opposite sides substantially]? greater than the diameterof the lamp bulbs employed, may be completely subjected to the'effects'of infrared rays from the lamp without the necesi s-it'y of' employingmultiple rows, or."'banks,-.. of lamps as is nowconvention'al practica.Theasav= ing is, of course, not only intheamount of" elec;- tricalenergy consumed foraparticularroperatibnz but is also material from. thestandpoint. of 'costof equipment;

Thepresent invention deals particularly: with a reflector-for infrared"my equipment by means of which the above desirable characteristics areobtainable.- Furthermore, th'ezreflector' of the present inventionisform'ed' in zlengths such that any desirablenumber'of infrared raylampsmay be mounted inlaterally."spaced 'relation with respect to eachother over the: length. of' a single such reflector; thus:-elimin'atin'gthe" necessity of forminga separate reflector.for-cooperation with eaclilamp' as is now commonv practice Additi'onally; Su'ch refl'ec'tols areso constructed and arranged that they maybe' positi'onedi m1 edge toedge relationship with respectlto: each other in banksofany'desired'length; and. height and'at suitable angles wi-tlir'esp'e'ctl t'o each 1' otherso as toenable -themato be adapted; to anysize: and shape of object to be treated by infrared rays.

Thus; the construction; is;such.xas.itocprovide a standard: sectioniiforthe? reflectors; which section may" be economically manufactured: in:relatively long-lengths and simply-cut? to the length: desired in; anyparticular installatiomand a. plurality of which lengths: may be readilyassociatedixwith each other: to' formibanks of; lamps" ofiany width 'orheight.

Ref'e'rringinow to: the accompanyingdrawings and particularly to'Fig; 1,there is. shown'ame flector indicated generally at l'U-form'edtfrom: asingle piece of sheet m'et'al andihaving a: base-or bottom wall l2 andopposite side: walls I4; It willbe understood that the View in Fiig; 1"is a transverse i, section through such reflector and that in' practice;the reflector is elongatedi and therefore of more or less trough: likeconformation.- While. the'b'as or bottom walLlZmay be slightly curvedorlfla't and: similarly the sidewalls F E-"maybeslightly'curvedlor'flat, theyarezpreferably flat as shown in; order to?obtain: a more evenly distributedo and controlled? reflection". of lightfth'erefrom; Likewise; the; base? or' bottom wall [2 may'bejoinedttd'the sidewalls M-rthroug-h ara'di'us of greater: or: lesser"extent; these: walls beingslio'wn'zin theed'rawings as: having: ai subst'anti'ally sharp-corner betweenthem; The 1' free edgesiof tli'exsidewalls- I 4 are preferably provided with; a relatively'inarrow but'oontinuousfiange .16

I bent outwardly-ttherefrom .and: formed; integrallytlrerewittninotionlwtozaidiimrigidifyingrthe struce ture but for anadditional purpose which will hereafter be apparent.

An infrared ray lamp bulb I8 is positioned with its axis in thelongitudinal central plane of the reflector. While it may be supportedin any suitable or conventional manner, in the particular case shown asheet metal box or conduit 20 of rectangular section is mounted inspaced relation with respect to and in back of the base or rear wall:l2: and isv provided with aipair. of? forwardly projecting legs 22,theiree" ends of which are bent outwardly and rigidly secured in contactwith the rear wall 12 of the reflector by means of.:s'crews-:24;. Themember 20 has fixed interiorly thereof. a socket 25 of conventionalconstruction ih'which-the threaded end of the bulb I8 isadaptedto-bexreceived. The rear wall I2 is, of course, apertured in linewith the socket 25 in the member ZU-so that its stem portion may beprojected therethrough. The member 2:) and the socket 25 carried.thereby is positioned at such. distance behind the rearxwall l 2 thattheray emitting ele.- ment of the-lamp l8; ..shown in the conventionalform. of: a coilLZfig. isr-positioned; a. material distance5rearwardlyofitheplane: ofthe forward edges ofzthe sidewalls Me. It isipreferablethat the last mentioned relation: exist regardless of the particularsize of the lamp lwS-employed'where suchrlamp isof the type shown-havingatransparentbody devoid of reflectingv material forming a part thereofand the presence: of WhiChzWOU-ld prevent direct projection of the raysof heatfrom the lamp upon'the reflection: I0 Theprojection of theforward: edges of-the: side Wa1ls M beyond the point of heat" ray;emission. from the lamp M31 is. necessary to obtain-full advantage-ofthe present-invention, but even in'caseswherea lamp ofsuch'shape'orsize-isemployed-that the point of" heat rayemissionthereof-z lies outwardly be.- yond the planeof'the freeedgesofthe-side walls oftherefiectorcertainmaterial advantages of thepresent'invention are .stillobtainable.

Where the-point; of. heat. ray emission. of the lampyshownas' the'coil2fi inlthe. lamp l-S in Fig. 1; lies a: sufficient distance inwardlyfromv the plane. of the free: edges .ofcthe. side walls. M, and the-sidewalls M are arranged at the-proper. angular relation with respect to theaxis-of; the lamp l8; then, asbroughtout in::Fig. 1, the opposite endsof an. object, such: as. 2 8, tobeheated by the; lamp. I8 andspacedifrom. each. other. by a distance;greater'zthanthe diameter ofthelamp l 8, .may be heated. thereby. In. suchcase, the opposed 'faceof. thesobject28- may receive direct rays from the lamplii as-wellas-rays therefrom ly and: centrally. in: front thereof...

Obviously; by positioning two lamps, andv their cooperatingreflectors-in opposed. and. spaced relationship with-respect..to..each..otl1er as indicated. in Fig;- 2, thenvwhen.amobflect such; as the object 28- of Fig. 1,. anobjectof. squaresection such as indicatedby dotted lines 341 inFig. 2, a round objectsuch; asindicatedz at. 32 in Fig. 2, oruany othershaped, object-whenpositioned. centrallyii w-ith .respect to .-.the...-.axis..-of thelamp": and

;wheniofitgreatenzvertical dimension; thanrthe di the only differencebeing that the side walls l4 of the reflectors l shown in Fig. 2 arebent outwardly at a greater degree with respect to the central plane ofthe reflector than in the construction illustrated in Fig. 1. Thisfeature of being able to bend the side walls I4 with respect to the basel2 so as to vary the angle in question is one of the advantages of thepresent inven 'tion as in such case reflectors having side walls atvarying angles to the base or rear wall l2, or to the lamp axis, may beprovided from standard size and shape reflectors. This is soparticularly in view of the fact that the reflectors H) are preferablymade of relatively light gage metal,

diffusion of rays from the lamps l8 reflected from the side walls 14 maybe varied by simply varying this angle in the manner above described.

Although, in the broader aspects of the invention, the reflectors l4 maybe formed from any suitable material having the desired light reflectingcharacteristics or having a surface imparting such characteristics toit, they are preferably made from aluminum or aluminum alloy having aspecular finish having a reflectivity in the neighborhood of 80% ormore. It has been found that by the use of such material the reflectorsID are relatively cheap and an extremely effective reflecting surface isprovided.

It will, of course, be appreciated that in actual practice very fewinstallations will be made comprising a single reflector l0 having oneor more bulbs such as l8 mounted in cooperation therewith, or a singlepair of reflectors l0 each with one or more bulbs such as 18 mounted incooperative relation therewith as shown in Fig. 2. The reason for thisis that most installations will be such as to permit a relatively widevariation in size and shapes of objects to be treated thereby and insuch case an arrangement of the general character shown in Fig. 3, orthe equivalent, will ordinarily be resorted to.

Referring to Fig. 3, it will be noted that in this case there are twobanks of reflector and lamp assemblies arranged in opposed relationshipto each other on opposite sides of a monorail conveyor indicatedgenerally at 40. In this case, each bank of lamps and reflectorsincludes six horizontally extending parallel reflectors l0 arranged insuccession one above the other with the adjacent flanges H inoverlapping relationship with respect to each other and secured togetherby -means of suitable fastening devices such as sheet metal screws 42.The four center reflectors l0 are arranged with the axes of the lamps18, or

'of each opening 44.

their central planes, horizontally so as to direct the rays of heattherefrom generally in a horizontal direction except, of course,concentrated and/or diffused, as explained in connection with Figs. 1and 2. The lower reflector of each bank is arranged with the centralplane thereof, or the axis of its various lamps l8, directed inwardlyand upwardly, in the particular case shown at approximately to thehorizontal. Similarly, the upper reflector ll! of each bank is arrangedwith the central plane of the reflector, or the plane including the axisof the lamps l8, directed inwardly and downwardly, shown in theparticular case illustrated as approximately at 45 to the horizontal.

It will be understood that each bulb l8 in the .construction illustratedin Fig. 3 is supported with respect to its reflector It in identicallythe same general manner as illustrated in Figs. 1 and 2, and it willalso be understood that in the arrangement shown in Fig. 3 eachreflector It) will be relatively elongated and have a plurality of lamps58 associated in spaced relationship with respect to each other over itslength. This feature is brought out in Fig. 4, which is a face view ofone Of the banks shown in Fig. 3 except that the lamps 18 have beenremoved, and from which it will be noted that each reflector I0 isprovided with eight openings 44 arranged in equally spaced relation withrespect to each other over the length of the reflector and through eachof which the stem of a lamp [8, or the equivalent, is adapted to beprojected for reception in a socket therefor, one arranged directly tothe rear Accordingly, in the particular arrangement shown, each bank oflamps shown in Fig. 3 will include 48 lamps when a lamp is inserted ineach of the sockets.

While the reflectors l0 and lamps is, or the equivalent, may besupported in the arrangement illustrated in Figs. 3 and 4 in anysuitable manner, in the particular case shown by way of illustration,each bank includes an end frame comprising a vertical angle member 46suitably secured as by welding at its lower end to a hori zontallydirected member 48 mounted upon a pair of spaced casters 50. Anangularly disposed angle iron 52 arranged with its face in a planeperpendicular to the central plane of the lower reflector l0interconnects the members 46 and 48 outwardly of their first describedpoint of attachment and not only serves as a brace for the joint betweenthem but for the purpose of supporting the lower reflector l0 and lampscarried thereby as will be appreciated. A short angularly directed angleiron 54 directed upwardly and inwardly from the upper end of each member46 is suitably secured thereto by welding or the like and serves thesame purpose as the members 52 in the support of the correspondingreflector l0 and lamps l8.

In the construction illustrated in Figs. 3 and 4, the members 20 firstdescribed are assumed to be elongated channel sectioned members intercomnecting the members 46, 52 and 54 at opposite ends of each bank so as torigidly interconnect them and serve as a means for supporting the inFig. 3 and in close but spaced relationship with 78 respect .to eachother, they cooperate to form fromeach other, and. front the floor;provide for .1

theready'flow of air'b'e'low ithe and between them -into the centralportiontof'the oven Where such airgbeing he'ate'd'from contact with thereflectors I and articles being treated may i freely escape upwardlybetween the opposede'dges of the upper V deflectors-Ill. Thisispointedout bythe arrows 58 in Fig. 3 showing thelflowof'such air. This "fiow'of air is oft'en important, particularlywhere thebanks of lamps areemployed for drying a coat of paint or enamel, or the like, on'the sur-"fa'ce' oran ob'je'chias the lampsdrive oil the volatile fluid of thepaints-'orwenamel'and the-flow'of air carries this away, therebyconstantlyproviding a supply of fresh air Whichmaymore readily absorbsuch volatile fluids.

It "will be appreciated thatinpracticethe refl'ectors may become very.hot: and this is particul'arly' sowhere the .lamp bulb's ls-or theirequivalent are-riot the'typeiincorporating the reflector 'sur'fa'ce as'anintegral part thereof. Evenin the flatter case they usuallybecomeveryhot because "ofreception'of light rays 'fromthe lamps of theopposite bank. Therefore, it is desirable to provide a'fre'e'flow oi'airparticularly over the back surfaces of the reflectors 410 soas'to'dissipate such heat and prevent any deleterious effectsthere'oforr the wiringfor the various lamps. In the presentcase, the"rear faces of the reflectors lllare open to the surrounding air so thatsuch --air in "being heated may freely flow upwardly ove'r'the backs ofthe reflector, as indicated'by the arrows 58 and carrythe heat away.

An important advantage-of the present invention is that inheatingobjects passed through opposed banks of thel'ampssuch as those shown-"in Fig. 3, the :am'ountof electrical energy re- "quired for .heatin theobjects to the desired extent may bekept at a-minimum. Where the"objects to 'be treated are-of such depth, as for 'instan'cein thef'caseof the article Ell illustratedinFig. 3, that its upper 'end'is at alevel with or -above'the upper edge ofthe second from the top reflectorin each bank, and the bottom edge is on the level with 'or'ibelow thelower edge from 'the second from/the bottom reflectorin "each "bank,then of. course "all of the lamps 18 in such "banks must be energized:if all the surfaces of theobje'ot 6-8 are to receive the rays ofheat-from th'e'lamp and be affected thereby. On-the other hand, 'if anobject such as indicated by dotted dines at 62 is the object tolea-treated-and which object '52 is of less vertical height than thewidth of two-reflectors It then, as illustrated at *Fig. 3, it may be sosuspended from the conyeyordt that its-upper edge is below the upperedge of one reflector of each bank" and its lower edge is: above theloweredge of the next-adjacent -reflector of'each bank, so that inthiscase only the lamps i8 in two-reflectors H) of each'bank arerequired to he energized-in. order to com-- .flpletely cover allsurfaces of the object 62. On the other hand, if an objectsuchasillustrated by dotted lines at 64 in-Fig. '3 is-to-be treatedbetween the two-banksof lamps and --its vertical dimension is less-thanthe width of -the open side;- of la single'reflector Hl, then itmaybe'arranged 2in substantiallypf the same relation as the obiiects and 32-:Fl'g. -i2, .and as brought out :Fig. 3, "so that the lamps in only oneirefle'ctor i111 598311 k are quired 't0 "be energized answers 8 cover-all surfaces of the object #64 to be treated.

.It'i's to be particularly hoted that-with-infrared ray lamp equipment:as heretoforeproduced and having lamps arranged in banks as in thegeneral manner illustrated in Fig. =3,- it would be necessaryinthetreating ofobjects such as-E2, and by shifting the same verticallyfrom the position shown, to employ at least three rows of lamps in eachbank-and in order to treat-anobject such "as "64 to employ at leasttworows. Thus, the possible relative saving in cost of electrical energyby the use'of the present invention will be appreciated. Where, as aboveexplained, the size of the object being passed between the oppositebanks of lamps-shown. in Fig. 3, or their equivalent, issuch as topermitonly'a portion 'ofthe various rowsv of lampsin each bankto-beutilizedin. properly treating --'it, then the 'efiect of the remaining rows oflamps-may be eliminated in anysuitablemanner. For instance, the lamps P8of each other rows may simply be removed. On the other hand, however, aswitch is preferably providedin thecircuit for each row of lam-ps l8 "sothat by simply opening certain such switches any desired row or rowsnlay be deenergized. 'In thismanner, the opposed banks of lamps'may bequickly conditioned to process any desired size of object capable ofbeing received between the opposite banks of lamps.

a As previously mentioned, while the-reflectorof the present inventionis probably more efficient when employed with a lamp of therelative sizeillustrated in Figs. 1, .2, and 3, and which lampis there shown asthetype commercially-known as the G-3Q,and while, of course, suchreflectors may be made in any size'so as'to be correspondinglyassociated with-other sizes of infrared ray lamps, other relative sizesof lamps may, of course, be used with anyparticular sizerefl'ector. Thisis brought out in -Figs.'5, 6, '7, and- 3, in which lamps of asized-iiieren-t irom the 6-30 size, shown as a lamp +8 in theprevious'figures, is illustrated with thesame relative size ofreflector. For instance, in Fig. 5a lamp commercially known as G-25 isshown in association with areflector H3 assumed in this caseto be thesame sizeas the reflectors previously shown. This lamp is slightlysmaller than the G-SO lamp, shown as :a lamp E8 in the previous figure,and the relative relation of the same with respect to the reflector I9is thus indicated. In Fig. 6 an infrared ray lamp commercially known astype F's-30 isillustrated; in Fig. 7 an infrared ray lamp of a typecommercially known as'type (3-40 is shown; and in Fig. 8 an infrared raylamp of atype commercially known as type It -40 isshown. These lamps allvaryin'size from the lamp of the type G-30 and the relative relationwith the same size reflector as employed with the latter type lamp intheprevious figures is illustrated. The advantages above describedare-all realized to a greater or lesser extent in connection'with allthese various types of lamps, orot-her types, but in the case of lampsoftheR-eo type or similar lamps which incorporate their own reflectingsurfacesthen, of course, the rays fromthe lamp itself will not bedirectly reflected from its own reflector I!) but the rays therefromwill bepropected to the opposite'ban-k of lamps and there bare-reflectedin a manner similar to'thatabov e described.

Having thus described "my invention and the advantages thereof, what Iclaim by Letters Patent is:

Infrared;rayequipmentzeompnsinginrcombmctlon a relatively elongated onepiece trough-like member formed from sheet aluminum having a specularfinish and comprising a relatively fiat base and a pair of opposedoutwardly diverging substantially flat side walls projecting from theedges thereof, and terminating at their free edges in laterallyoutwardly directed flanges, said sheet aluminum being of such athickness as to permit the angularity between said side walls and saidbase to be readily varied between 30 and 45 with respect to the centralplane of the reflector by bending the side walls with respect to saidbase, and the angularity of said flanges with respect to such side wallsmay be readily varied by bending said flanges with respect to said sidewalls, and an infrared ray lamp supported in fixed relations withrespect to said reflector with the infrared ray emitting element thereofapproximately centrally of the central plane of said re- REFERENCESCITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 908,838 Brown Jan. 5, 19091,400,859 Brown et a1 Dec. 20, 1921 2,042,855 Merklein June 2, 19362,263,866 Barber Nov. 25, 1941 2,317,426 Wilson Apr. 27, 1943 2,355,459Miskella Aug. 8, 1944 Certificate of Correction Patent N 0. 2,497,676February 14, 1950 RALPH W. LASHELLS It is hereby certified that errorsappear in the printed specification of the above numbered patentrequiring correction as follows:

7 Column 7, line 6, after the word below strike out the; column 8, line21, for each read such;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Oflice.

Signed and sealed this 13th day of June, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents.

Certificate of Correction Patent No. 2,497,676 February 14, 1950 RALPHW. LASHELLS It is hereby certified that errors appear in the printedspecification of the above numbered patent requiring correction asfollows:

Column 7, line 6, after the word below strike out the; column 8, line21, for each read such;

and that the said Letters Patent should be read with these correctionstherein that me same may conform to the record of the case in the PatentOffice.

Signed and sealed this 13th day of June, A. D. 1950.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents.

